Steffon Armitage, right, supports James Haskell in the match against Italy in 2009. Armitage won the last of his five England caps in 2010. Photograph: Russell Cheyne/Reuters

Life goes on, even in a week when Jonny five brings down the curtain on a sporting career as glorious and admirable as most of us will ever witness. It seems almost sacrilegious to broach any other rugby-related topic in the same breath as saluting the departure of a player who could have stepped out of a Burne-Jones painting, sword and breastplate glinting, captioned by Bunyan: “Who would true valour see / Let him come hither / One here will constant be / Come wind, come weather / There’s no discouragement / Shall make him once relent / His first avowed intent / To be a pilgrim.”

English rugby has never had a player – a pilgrim devoted to humble self-realisation on and off the pitch – like Jonny. But it does have the newly crowned European player of the year, a remarkable honour for Steffon Armitage and one immediately greeted with the news that he has not been selected among the members of Stuart Lancaster’s latest England touring party, the remainder of whom embark for New Zealand on Monday.

To secure his individual award, Armitage fended off competition from his Toulon team-mate Juan Smith and Saracens’ Schalk Brits, to mention only players who took part in last weekend’s Heineken Cup final. On Friday Lewis Moody, writing in the Independent, described him as “the best back-rower England have”, and you would think that a World Cup-winning flanker with 71 caps ought to be able to recognise excellence in that particular sphere of endeavour, however many bangs to the head he took in the course of his own indecently courageous career.

Yet Armitage is excluded from an injury-depleted squad through the application of the RFU’s policy of not selecting those who play their club rugby abroad, no matter how distinguished their feats in foreign colours. Even outside the Armitage household, this provoked responses ranging from bemusement to derision.

You might think, particularly with a Rugby World Cup at home only a year away, that England would be delighted by the availability of a player so central to the achievements of star-studded, multi-national Toulon, the Real Madrid of European rugby. In the case of the younger Armitage, we have a natural No7 who can wear the No8 jersey for his club but still perform his tasks at the breakdown – the critical zone of modern rugby – with something of the skill of Richie McCaw, the key member of the last side to win international rugby’s greatest honour.

The irony is that the exclusion comes at a time when an examination of the squads for the forthcoming football World Cup in Brazil reveals that once again, by contrast with the other leading nations, none of England’s team are employed by clubs based on home territory– and only one, Celtic’s Fraser Forster, does not play in the Premier League. Few people believe this to be a good thing. The prosperity of the English league is the most significant factor in keeping them at home, but so is the feeling abroad that they are not, in general, as fully developed as players and people as, say, their German or Spanish equivalents, neither as skilful nor as adaptable to a new culture.

This is not an entirely new phenomenon, but it does deprive Roy Hodgson’s squad of the sort of broader experience gained by Kevin Keegan in Germany, Trevor Francis and Paul Ince in Italy, Gary Lineker in Spain and David Beckham during his various wanderings. Lancaster, you would think, might feel that his squad would benefit from the extra perspective.

But no. England believe the best way of defending the integrity of English clubs and the Premiership is through a policy of protectionism, discouraging the most talented players from listening to overtures from abroad. In particular, of course, the players must be persuaded to remain deaf to advances from France, where the more liberal salary cap operated by the clubs of the Top 14 tournament enables Toulon, Toulouse and Clermont Auvergne to send their recruiting parties far and wide. In some eyes this makes England look as desperate as Wales, despite having a far greater player pool and a sounder economic base.

Since Lancaster took over in 2011, the unpretentious Cumbrian head coach has proved a positive force. Sweeping away the debris of the sadly ruinous Martin Johnson regime, he restored a sense of calm and of firm priorities, chief among which was the development of a core group of players. But that should hardly preclude a willingness to bend every now and then in order to accommodate the unpredictable arrival of talent superior than that already available within the squad.

Understandably, perhaps, it took him a long time to be convinced of the wisdom of readmitting the gifted but formerly wayward Danny Cipriani. What happens in Auckland, Dunedin and Hamilton over the next three weeks will perhaps tell us more about Lancaster than about Cipriani. But the gesture showed him to be flexible.

It is a mystery why that flexibility does not extend to Armitage, given that a loophole was carefully built into the exclusion policy, which can be varied in “exceptional circumstances”. Goodness knows what else Armitage needed to show to qualify as an exception. It certainly seems unlikely that Lancaster, himself a former back-row forward, would dispute Moody’s assessment.

There must be a suspicion that his inclusion might be seen as interfering with the head coach’s carefully constructed platform for an assault on next summer’s tournament. His captain, Chris Robshaw, plays essentially the same role as Armitage, even when the latter wears a No8 on his back. Robshaw is a head coach’s dream, reliable and consistent on the pitch as well as giving the squad an acceptable public face: no small attribute. Were the Toulon man to outshine the captain on the field, awkward decisions could provoke internal tensions. From what one knows of Lancaster, he is not a believer in such tensions producing a constructive outcome.

A chink of light was allowed to peep through in his remark this week that Armitage’s candidacy might be considered closer to the World Cup. Given his commitment to joined-up team building, however, it can never be too soon to call on the best available talent.

Much can happen between now and September 2015, but it seems unthinkable that the hosts will mount a challenge without a player who, if his form and fitness hold, could prove as decisive a presence as the man whose drop goal in Sydney 11 years ago took England to the heights they are so desperate to regain.

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